From the way you worded your question I take it that you are talking about penis growth, not height, but the answer would be the same for either. Masturbation does not effect your penis size or your height or slow down the rate of growth.

Lots of people have heard all sorts of crazy stuff about masturbation, like that it can cause diseases, interfere with growth, cause mental problems, lead to blindness, or stop a person from having children. But those things aren't true.

ôReligion is an insult to human dignity. With or without it, you'd have good people doing good things and evil people doing bad things, but for good people to do bad things, it takes religion.ö-Steven Weinberg